Image sensors providing an image for a field of view are broadly used in vision applications such as surveillance, environment monitoring, robotic navigation and also Philips LumiMotion streetlamps wherein a streetlamp is turned on when presence of a person is detected.
These image sensors preferably provide a broad field of view while also being compact and inexpensive. Disadvantages of using a broad field of view are image distortion and loss of illuminance towards the periphery. These disadvantages always are present but are in particular noticeable when wide-angle and fisheye lenses are used.
While solutions are available for reducing these deficiencies, most of these solutions add significantly to the costs, e.g. in the image sensor by having to increase pixel resolution at the periphery by means of customized lenses, and/or in the means for analysing the image by having to use advanced video processing which demands calculating power with increased demand for memory storage etc.